Rootwire Amalgam is a mythic Artifact Creature — Golem card from The Brothers' War (BRO), collector number 203. Current market price: $0.42 (foil $0.48), TCGplayer market prices via Scryfall.
Prototype {1}{G} — 2/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.) {3}{G}{G}, Sacrifice this creature: Create an X/X colorless Golem artifact creature token, where X is three times this creature's power. It gains haste until end of turn. Activate only as a sorcery.